Game Hacking Techniques

Overview

This skill covers game hacking techniques documented in the awesome-game-security collection, including memory manipulation, rendering overlays, input simulation, and exploitation methods.

Core Concepts

Memory Manipulation

• Read Process Memory (RPM)
• Write Process Memory (WPM)
• Pattern scanning
• Pointer chains
• Structure reconstruction

Process Injection

• DLL injection methods
• Manual mapping
• Shellcode injection
• Thread hijacking
• APC injection

Hooking Techniques

• Inline hooking (detours)
• IAT/EAT hooking
• VTable hooking
• Hardware breakpoint hooks
• Syscall hooking

Cheat Categories

Visual Cheats (ESP)

- World-to-Screen transformation
- Player/entity rendering
- Box ESP, skeleton ESP
- Item highlighting
- Radar/minimap hacks

Aim Assistance

- Aimbot algorithms
- Triggerbot (auto-fire)
- No recoil/no spread
- Bullet prediction
- Silent aim

Movement Cheats

- Speed hacks
- Fly hacks
- No clip
- Teleportation
- Bunny hop automation

Miscellaneous

- Wallhacks
- Skin changers
- Unlock all
- Economy manipulation

Overlay & Rendering

Overlay Methods

• DirectX Hook: D3D9/11/12 Present hook
• Vulkan Hook: vkQueuePresentKHR hook
• OpenGL Hook: wglSwapBuffers hook
• DWM Overlay: Desktop Window Manager
• External Window: Transparent overlay window
• Steam Overlay: Hijacking Steam's overlay
• NVIDIA Overlay: GeForce Experience hijack

Rendering Libraries

• Dear ImGui: Immediate mode GUI
• GDI/GDI+: Windows graphics
• Direct2D: Hardware-accelerated 2D

Memory Access Methods

User-Mode

- OpenProcess + ReadProcessMemory
- NtReadVirtualMemory
- Memory-mapped files
- Shared memory sections

Kernel-Mode

- Driver-based access
- Physical memory access
- MDL-based copying
- KeStackAttachProcess

Advanced Methods

- DMA (Direct Memory Access)
- EFI runtime services
- Hypervisor-based access
- Hardware-based (FPGA)

Driver Communication

Methods

• IOCTL-based
• Shared memory
• Registry callbacks
• Syscall hooks
• Data pointer swaps

Common Patterns

// Data pointer swap example
NtUserGetObjectInformation
NtConvertBetweenAuxiliaryCounterAndPerformanceCounter
Win32k syscall hooks

World-to-Screen Calculation

Basic Formula

Vector2 WorldToScreen(Vector3 worldPos, Matrix viewMatrix) {
    Vector4 clipCoords;
    clipCoords.x = worldPos.x * viewMatrix[0] + worldPos.y * viewMatrix[4] + 
                   worldPos.z * viewMatrix[8] + viewMatrix[12];
    clipCoords.y = worldPos.x * viewMatrix[1] + worldPos.y * viewMatrix[5] + 
                   worldPos.z * viewMatrix[9] + viewMatrix[13];
    clipCoords.w = worldPos.x * viewMatrix[3] + worldPos.y * viewMatrix[7] + 
                   worldPos.z * viewMatrix[11] + viewMatrix[15];
    
    if (clipCoords.w < 0.1f) return invalid;
    
    Vector2 NDC;
    NDC.x = clipCoords.x / clipCoords.w;
    NDC.y = clipCoords.y / clipCoords.w;
    
    Vector2 screen;
    screen.x = (screenWidth / 2) * (NDC.x + 1);
    screen.y = (screenHeight / 2) * (1 - NDC.y);
    
    return screen;
}

Engine-Specific Techniques

Unity (Mono)

• Assembly-CSharp.dll analysis
• Mono JIT hooking
• Il2CppDumper for IL2CPP builds
• Method address resolution

Unity (IL2CPP)

• GameAssembly.dll analysis
• Metadata recovery
• Type reconstruction
• Native hooking

Unreal Engine

• GObjects/GNames enumeration
• UWorld traversal
• SDK generation (Dumper-7)
• Blueprint hooking

Source Engine

• Entity list enumeration
• NetVars parsing
• ConVar manipulation
• Signature scanning

Input Simulation

Methods

• SendInput API
• mouse_event/keybd_event
• DirectInput hooking
• Raw input injection
• Driver-based input (mouclass)

Kernel-Level

• Mouse class service callback
• Keyboard filter drivers
• HID manipulation

Anti-Detection Techniques

Code Protection

• Polymorphic code
• Code virtualization
• Anti-dump techniques
• String encryption

Runtime Evasion

• Stack spoofing
• Return address manipulation
• Thread context hiding
• Module concealment

Development Workflow

External Cheat

1. Pattern scan for signatures
2. Read game memory externally
3. Process data in separate process
4. Render overlay or use input simulation

Internal Cheat

1. Inject into game process
2. Hook rendering functions
3. Access game objects directly
4. Render through game's graphics context

Learning Resources

Communities

• UnknownCheats
• GuidedHacking
• Game Hacking Academy

Practice Targets

• PWN Adventure (intentionally vulnerable)
• CTF game challenges
• Older/unsupported games